1. Field of the Description
The present description relates, in general, to systems and methods for fabricating skins or skin systems for use with robotic and other characters, and, more particularly, to a method (and system for implementing such a method) of fabrication for creating lightweight but durable skin systems for robotic or animatronic characters in a manner that is easily repeatable (e.g., allows an identical skin to be formed over and over), is useful with relatively large characters or figures, and is suited for quick and effective modifications to a skin system design (e.g., when a designer wants to change the stiffness, the outer texture, or another skin parameter, the method allows changes to be made in a simple, timely, and inexpensive manner).
2. Relevant Background
Durable materials that are often also flexible and elastic such as plastics and rubbers are used in many applications to create coverings or skins that are applied over an internal physical support structure or skeleton. For example, skins or skin systems are used to create realistic models of humans, animals, and characters, and, when combined with robotics, such models may accurately simulate live beings.
Robotics involves the design and use of robots to provide programmable actuators or drivers to perform tasks without human intervention, and there have been significant demands for robotic devices (or robots as these terms may be used interchangeably) that simulate humans, animals, and other living beings or characters. These robotic characters are relied upon heavily in the entertainment industry, such as to provide special effects for movies and television and to provide robots for use in shows and displays in amusement or theme parks. For example, robotics may be used to provide a character in a theme park ride or show that repeats a particular set of movements or actions (e.g., programmed tasks) based on the presence of guests or a ride vehicle or another triggering event.
While many advances have been made in realistically simulating the physical movement and facial movement of a character, problems with maintaining a realistic or desired movement or facial animation still occur when the robotics (e.g., internal components of a robot including mechanical/structural portions as well as software, hardware, power systems, and the like) are covered with a skin or skin system. For example, a robot used to simulate a particular creature would be covered with skin or a covering assembly to imitate the natural or desired covering for the creature such as skin and fur/hair for many creatures, clothes for some creatures such as humans or characters (e.g., characters from animated films or television or puppets), or a more fanciful covering system such as a metallic suit or any other desired covering. In simulating humans or human-like characters, the robotics are typically covered in a skin that is fabricated of flexible material to move naturally with the underlying robotics. The skin may be formed of a rubber material or a silicone that is attached or anchored to the mechanical actuators or drivers of the robotic system, and the skin is configured to have an outward appearance similar to the character or creature being simulated by the robot. To simulate animals or characters that may be real or imagined, the outer surfaces of the skin may be designed with a patterned or textured outer surface, e.g., to have scales or other features.
Typically, a skin system for a robot is made using a manual process relying on skill and experience of the craftsperson creating the skin and requiring many man-hours to prototype and later fabricate based on the prototype. In an exemplary process, a sculpture is created, such as from clay or other moldable/shapeable materials, to represent the exterior skin shape (e.g., a person's face, a character from a movie, and so on). The sculpture is then molded, and sheet wax or a layer of clay is laid by hand into this exterior mold to define a desired thickness for the exterior skin layer. An interior core is then fabricated by hand such as by using fiberglass and resin, and this core may be configured to include skin attachment points to allow robotics to later be attached or anchored to the skin. A fiberglass or similar material is used to form a mold from this core, and hard shells, e.g., fiberglass shells to support the skin when the robot is later assembled, are then created from this core mold.
An exterior skin can finally be formed by pouring a rubber or other flexible material into the gap between the exterior mold (with the sheet wax removed) and the core mold. After it is set, the skin is removed from the molds and placed on the supporting or hard shell(s) and attached to portions of the robotics. If modifications are desired such as to further texture a surface or to increase flexibility, the formed skin may be cut or otherwise modified manually (e.g., cut away grooves at or near a joint to increase flexing of the skin if the skin from the mold is too stiff or rigid).
As will be appreciated, conventional molded-skin approaches are very time consuming, are heavily dependent upon the skill and experience of the artisan, and are very difficult to repeat (e.g., even the same artisan will likely produce differing molds and skin systems when the process is repeated). There remains a need for improved methods for fabricating skin systems or assemblies for robotics and for other applications that involve covering a support structure with a covering or skin. Preferably such fabrication methods would be less labor-intensive than existing techniques and would support design and prototype efforts such as more efficient alteration of component shapes, sizes, materials, and the like.